1. Field of the Invention
The present invention relates to methods and apparatus for automatically washing a series of folding chairs.
2. Discussion of Background
Folding chairs are chairs that fold to an essentially flat configuration, usually by lifting the front of the seat from a horizontal unfolded position to a vertical folded position as the legs pivot with respect to each other. Folding chairs are often used in large numbers for events such as graduation ceremonies, weddings, concerts and so on. At these events, foreign matter can soil the chairs. "Foreign matter" includes traces of food and beverages, fingerprints, scuff marks, mud, bird droppings, tree sap, grass stains, blades of grass, and so on; essentially foreign matter is any matter not found on a clean chair.
Currently, folding chairs are cleaned manually in one of two ways. The first method involves the use of a brush and hose. The second uses a pressurized hose. Typically, a worker can clean 30-40 chairs per hour. The chairs are brought to a central location, for example, a rental agency or warehouse, where they are cleaned before sending them out again because cleaning them at the event location requires more time than practical for a large number of chairs. Then the chairs are either stored for the next use or sent to a new event site.
Although there are a number of apparatus for cleaning a series or set of objects, such as commercial dishwashers, car washes, grocery carts (U.S. Pat. No. 3,698,029), cafeteria trays (U.S. Pat. No. 4,281,675), poultry shackles (U.S. Pat. No. 4,042,993), beverage cases (U.S. Pat. Nos. 3,675,665 and 3,018,200), bottles (U.S. Pat. No. 3,545,024), eyeglasses (U.S. Pat. No. 3,464,080), applicant is unaware of any apparatus for automatically cleaning folding chairs, in spite of the fact that folding chairs are routinely used by the hundreds and thousands at events, and inevitably require labor-intensive to clean between uses.
Notwithstanding the fact that a significant effort is required to clean large numbers of chairs, sometimes between use at closely-timed events, the problem of cleaning chairs quickly and cheaply has long gone unrecognized; that is, the need for an automatic chair-cleaning apparatus has not heretofore been recognized, as indicated by the absence, for example, of apparatus for this purpose.
Moreover, once the fact that large numbers of folding chairs must be cleaned is recognized, it can be appreciated that cleaning folding chairs automatically presents several problems. For example, folding chairs are symmetric left to right but not top to bottom or front to back. Furthermore, because they tend to loosen with use, the seat will readily pivot from the vertical folded to the horizontal unfolded positions. To be really useful, an apparatus for cleaning folding chairs should be portable, so that it can be taken to a location where the chairs have been used. It should be operable from readily-available power and water supplies. It should be efficient so that a large number of chairs can be cleaned in a short amount of time so that on-site cleanup of the chairs does not take an inordinate amount of time. Therefore, there is a need for an apparatus for cleaning a series of folding chairs, an apparatus that washes chairs thoroughly, quickly and cheaply.